Experimental study on seismic performance of prefabricated replaceable beam-column connectors using double-sided angle steel

An innovative performance-reparability beam-column connection was proposed in this paper. Based on quasi-static test of two specimens without replaceable angle steel, five specimens with double-side angle steels and one specimen with one-side replaceable angle steel, the seismic performance of this new type of beam-column connector was analyzed. Through the analyses of destruction form, hysteretic loops, skeleton curves, cumulative dissipated energy, strength and stiffness degradation, residual deformation and re-centering behavior as well as the measured strains results of the beam-column connector, the effects of setting angle steel, initial prestressing, different flange thickness of the connector and replacement of angle steel on the seismic performance of the prefabricated beam-column connectors were examined. The results indicated that the seismic performance of this new type connector shown an excellent seismic behavior. Setting replaceable angle steel and increase the number of angle steel could effectively improve the seismic performance; The seismic performance repair could be achieved quickly by using of thicker angle steel after replacement; Reasonable initial prestress could effectively increase the ultimate load, initial stiffness, re-centering ability and the energy consumption of the specimens; Increasing the flange thickness of the connector could reduce the expansion degree of the flange. The mechanism of "elastic in the minor earthquake, self-centering in the moderate earthquake and replaceable in the major earthquake" could be realized well by rational design, and the repair of structure after earthquake can be solved easily by different very low-cost solutions. Based on the test results, a moment calculation method, which could distinguish the gap opening was proposed, and the calculated results agreed well with the experimental results.